Refine
Year of publication
- 2007 (149) (remove)
Institute
- Fachbereich Medizintechnik und Technomathematik (45)
- IfB - Institut für Bioengineering (29)
- Fachbereich Elektrotechnik und Informationstechnik (28)
- Fachbereich Luft- und Raumfahrttechnik (23)
- INB - Institut für Nano- und Biotechnologien (16)
- Fachbereich Wirtschaftswissenschaften (15)
- Fachbereich Chemie und Biotechnologie (14)
- Fachbereich Maschinenbau und Mechatronik (10)
- Fachbereich Energietechnik (6)
- Fachbereich Bauingenieurwesen (4)
Language
- English (149) (remove)
Document Type
- Article (94)
- Conference Proceeding (44)
- Part of a Book (6)
- Doctoral Thesis (2)
- Bachelor Thesis (1)
- Book (1)
- Lecture (1)
Keywords
- Führung (3)
- Leadership (3)
- Finite-Elemente-Methode (2)
- Actuators (1)
- Air purification (1)
- Aktor (1)
- Aktoren (1)
- Bauingenieurwesen (1)
- CAD (1)
- Clusterion (1)
IT Service Deployment
(2007)
Chain scattering parameters or T-parameters are a useful tool for calculating cascaded two-ports. With the increasing importance of mixed-mode S-parameters, a need for converting the T-parameters from their unbalanced form into a balanced form emerges for suiting both common and differential mode waves, as well as the mode conversion. This paper presents the derivation of the equations for transformations between mixed-mode S- and T-parameters for a mixed-mode two-port. Although derived in a way very similar to monomode T-parameters, no simplifications were necessary. Measurement results exemplify the quality of the T-parameter transformation under real-life conditions.
Solar Sail Kinetic Energy Impactor Trajectory Optimization for an Asteroid-Deflection Mission
(2007)
This work describes a procedure to yield attenuation maps from MR images which are used for the absorption correction (AC) of brain PET data. Such an approach could be mandatory for future combined PET and MRI scanners, which probably do not include a transmission facility. T1-weighted MR images were segmented into brain tissue, bone, soft tissue, and sinus; attenuation coefficients corresponding to elemental composition and density as well as to 511 keV photon energy were respectively assigned. Attenuation maps containing up to four compartments were created and forward projected into sinograms with attenuation factors which then were used for AC during reconstruction of FDG-PET data. The commonly used AC based on a radioactive (68Ge) transmission scan served as reference. The reconstructed radioactivity values obtained with the MRI-based AC were about 20% lower than those obtained with PET-based AC if the skull was not taken into account. Considering the skull the difference was still about 10%. Our investigations demonstrate the feasibility of a MRI-based AC, but revealed also the necessity of a satisfying delineation of bone thickness which tends to be underestimated in our first approach of T1-weighted MR image segmentation.
Handheld measurement device for field-effect sensor structures: Practical evaluation and limitations
(2007)
The most of conventional methods of air purification use the power of a fan to draw in air and pass it through a filter. The problem of bacterial contamination of inner parts of such a type of air conditioners in some cases draws attention towards alternative air-cleaning systems. Some manufacturers offer to use the ozone's bactericidal and deodorizing effects, but the wide spreading of such systems is restricted by the fact that toxic effects of ozone in respect of human beings are well known. In 2000 Sharp Inc. introduced "Plasma Cluster Ions (PCI)" air purification technology, which uses plasma discharge to generate cluster ions (I 0-14 ). This technology has been developed for those customers that are conscious about health and hygiene. In our experiments, we focused on some principal aspects of plasma-generated ions application - time-dependency and irreversibility of bactericidal action, spatial and kinetic characteristics of emitted cluster particles, their chemical targets in the microbial cells.
In: Advanced Engineering Informatics. Vol 21, Issue 1, 2007, Pages 67-83 http://dx.doi.org/10.1016/j.aei.2006.10.001 eds. J.C. Kunz, I.F.C. Smith and T. Tomiyama, Elsevier, Seite 1-22 Current CAD tools are not able to support the conceptual design phase, and none of them provides a consistency analysis for sketches produced by architects. This phase is fundamental and crucial for the whole design and construction process of a building. To give architects a better support, we developed a CAD tool for conceptual design and a knowledge specification tool. The knowledge is specific to one class of buildings and it can be reused. Based on a dynamic and domain-specific knowledge ontology, different types of design rules formalize this knowledge in a graph-based form. An expressive visual language provides a user-friendly, human readable representation. Finally, a consistency analysis tool enables conceptual designs to be checked against this formal conceptual knowledge. In this article, we concentrate on the knowledge specification part. For that, we introduce the concepts and usage of a novel visual language and describe its semantics. To demonstrate the usability of our approach, two graph-based visual tools for knowledge specification and conceptual design are explained.